Immunoprecipitation combined with microchip capillary gel electrophoresis for detection and quantification of β-galactosidase from crude E. coli cell lysate in bioprocess technology Authors

This Application Note describes the development of an immunoprecipitation method in combination with microfluidic on-chip analysis on the Agilent 2100 Bioanalyzer for sensitive, selective and quantitative detection of endogenous β-galactosidase in crude E. coli lysates. The effects of antibody selection and the importance of preclearing steps for sensitive and specific detection of the target protein are discussed. Quantification of β-galactosidase was achieved via an external calibration curve based on various spiking levels of pure β-galactosidase into E. coli lysate. Results proved the described approach to be quantitative over orders of magnitudes and highly reproducible.